[6][8] The anti-incumbency movement played a role in the ouster of a Pennsylvania Supreme Court justice and in the defeat of 17 incumbent state legislators in primary elections.

[5] The campaign was contentious; Diamond's supporters filed legal challenges against the campaigns of Joe Eisenhauer and Wanda Bechtold, who sought the Republican nomination, and successfully got their names removed from the primary ballot (due to a failure to timely file financial disclosure forms and a failure to obtain enough signatures, respectively).

[5] As a result of these challenges, Diamond was the only candidate on the ballot in the May primary, although Bechtold ran an unsuccessful write-in campaign.

[22] In July 2020, Diamond mocked a statement against discrimination against LGBT people issued by Levine, who is transgender, by copying-and-pasting her statement and replacing the term "LGBTQ" with the word "unmasked" to allege discrimination against what he called the "unmasked community" (people who refuse to wear masks during the COVID-19 pandemic).

Court documents state that one woman claimed Diamond "pushed her in the face seven times and scratched her under an eye" and "threatened to kill her if she disconnected the cable".

[35] The second woman to file for a PFA against Diamond told the courts that when she wouldn't leave his apartment, "he knocked her down and dragged her to the doorway."

[35] In 2014, members of the Lebanon County Republican Committee sent Diamond a letter asking him to withdraw from the race for House of Representatives, citing his "string of unsuccessful runs for office" and the apparent history of violence evidenced in court documents.

"[35] Pennsylvania State Senator David Arnold Jr. (also a member of the Lebanon County Republican Committee) said that Diamond had engaged in a "disturbing pattern of behavior" in which he "admits no culpability and makes light of it.